Potential use of immunobiotic lactic acid bacteria for the recovery of innate immune response in a cyclophosphamide-immunosuppression mice model

SALVA SUSANA; VILLENA JULIO; PACHECO VICTORIA; ALVAREZ SUSANA

Buenos Aires

Congreso; LVIII Reunión Anual de la Sociedad Argentina de Inmunología-XIII Jornada Científica del Grupo Rioplatense de Citometría de Flujo-3º Jornadas Argentinas de Inmunodeficiencias Primarias (SAP); 2010

Sociedad Argentina de Inmunología

Cyclophosphamide (Cy) is a drug commonly used in the cancer treatment because of its high toxicity on tumor cells. However, Cy induces myelosuppression leading to a state of immunosuppression with increased susceptibility to opportunistic infections. Previously, we demonstrated that the preventive treatment with immunobiotic lactic acid bacteria (LAB) improves the recovery of myeloid cells populations in Cy-treated mice. This work evaluated the ability of the preventive treatment with immunobiotic LAB to improve the innate immune response against Candida albicans (Ca) in Cy-treated mice. Different groups of Swiss-albino mice were fed Lactobacillus casei CRL431 (Lc431, 109 cells/d/mouse) or L. rhamnosus CRL1506 (Lr06, 108 cells/d/mouse) for 2 or 5 consecutive d respectively. After each treatment, these mice and untreated control mice (CG) received an intraperitoneal injection of Cy (150 mg/Kg). Later we analyzed the resistance to systemic challenge with Ca by assessing the survival of infected mice and pathogen count in blood, liver and spleen. In addition, we studied the innate immune response against Ca through the analysis of phagocytic cell counts in blood, and their recruitment to peritoneal cavity (pc), using both hemacytometer methods and flow cytometry. The preventive administration of Lc431 and Lr06 induced: a) The increase of the survival of Cy-treated mice infected with Ca (CG=40; Lc431=70; Lr06=60 %); b) The decrease of the pathogen number in infected tissues and its early elimination from liver and spleen; c) The improvement of leukocytes recruitment into the injury site (pc leukocytes CG=1,7±0,7; Lc431=6,0±0,5; Lr06=6,3±0,1 106 cells/L); and d) The increase of Gr-1+ cells in blood and peritoneal fluid (pc Gr1+ cells CG=2,1±0,6; Lc431=37,35±3,0; Lr06=35,0±2,4 105 cells/L). Therefore, the influence of preventive administration of LAB on innate immunity would be responsible, at least in part, of the increased resistance to infection by Ca.